The phrase "ultra-processed" has spent years attached to kibble in casual conversation. A new scientific review says that word has never actually been defined for pet food at all.
A review published in Frontiers in Veterinary Science examined pet food processing techniques against the human food classification system known as NOVA, and found the human definition doesn't transfer cleanly. The researchers aren't defending kibble. They're arguing the entire industry has been operating without a formal classification system — and that gap is exactly what's allowed it to avoid scrutiny this long.
Why Human Food Rules Don't Just Transfer
The NOVA system classifies human food by how much it's been altered from its whole-food state, with "ultra-processed" as the most industrial tier.
Applying that system directly to pet food runs into a structural problem: unless it's labeled for supplemental or vet-supervised feeding only, commercial pet food must be nutritionally complete on its own. A human snack food can be ultra-processed and nutritionally empty at the same time. A bag of kibble, by regulation, cannot be nutritionally empty — it has to meet AAFCO minimums for every life stage it claims to serve. That difference is real. It's also being used to wave off a conversation the industry would rather not have.
The Gap The Review Is Trying To Close
The researchers reviewed processing techniques used in dry kibble and canned pet food, alongside what's known about each method's health effects.
Their conclusion: pet food needs its own processing classification system, built for pet physiology instead of borrowed wholesale from human nutrition science. Right now, there's no standardized way to compare how heavily one bag of kibble has been processed against another. A product can market itself as "natural" or "premium" while running through the exact same high-heat extrusion process as a bargain-bin bag next to it on the shelf.
What Getting Classified Would Actually Change
A formal classification system would give owners something they don't currently have: a way to compare processing intensity across brands, not just ingredient lists.
That matters because digestive enzymes and nutrient availability change under high heat, regardless of what the label says about the source ingredients. Right now, two bags with nearly identical ingredient panels can put a dog's gut through very different processing loads, and there's no labeling requirement that would ever tell an owner that. The researchers frame this as a labeling and communication problem first — one the industry has had decades to fix voluntarily and hasn't.
Why This Took So Long
Pet food companies have had every incentive to avoid a classification system that grades processing intensity.
A formal system invites direct comparison, and direct comparison is exactly what mass-market kibble brands have spent decades marketing around. The review doesn't accuse anyone of hiding data. It simply points out that the absence of a standard has functioned the same way hiding data would — by keeping owners guessing.
Sources
Does the definition of human ultra-processed foods apply to dog and cat foods? A review of pet food processing techniques, their impact on health, and a call for pet food processing classification — Frontiers in Veterinary Science, 2026
KibbleFacts.com All rights reserved. Kibble Facts believes every dog deserves an advocate, and every dog owner deserves clear, trustworthy guidance. From uncovering what's really in commercial pet food to sharing practical tips on nutrition, wellness, behavior, aging, and the everyday joys of caring for your dog or cat, we're here to make pet care feel less confusing and a lot more empowering.
